The Mara Salvatrucha, or MS-13, is arguably the most notorious street gang in the Western Hemisphere and is so feared it has been left to run its own prison – the Penas Ciudad Barrios.

The maximum security prison located in the capital of El Salvador, San Salvador, houses only Mara Salvatrucha members and is guarded by prison guards and the El Salvadorian army from outside its gates. This ensures that its inmates stay behind bars but means they hardly meddle at all with the on-goings inside its walls.

The MS-13 – whose motto is “rape, control, kill” – was founded in the 1980s in Los Angeles by war-torn El Salvadoran immigrants, but has since been brought back to the country after repatriation.

The prison was originally built to house 800 members and is now home to 2,500 prisoners. It is run in essence by the inmates themselves, controlled by their own miniature society, complete with bakery, workshops, a hospital and rehab.

In 2013 a photographer from London, Adam Linton, was granted access to the Penas Ciudad Barrios gangland. He said, “The men stand around aimless with nothing to do except kill what seem like an infinity of minutes, hours and days.”

Linton also added, “The vast majority of the inmates are from the Barrios or slums. In El Salvador this is a place without hope or opportunity and the gang is the only real option. If the authorities catch you this is the place they literally dump you and forget about you – every inmate is made to feel just like that.”

The gang members have a distinctive look, they distinguish themselves with tattoos which cover their bodies and faces. Chillingly their ink denotes that they mark themselves for death as well as the membership of the gang they belong to.

Violence between street gangs is said to be soaring once again after the unprecedented truce between El Salvador’s main gangs – the Mara Salvatrucha and Barrio 18 – began to fall apart last year.

The country saw a peak in the number of murders in August with 911 homicides, making it its deadliest month since the Civil War came to an end over two decades ago in 1992.

It’s no secret that prison is a dangerous place – the fights, the stabbings – the guards fear of the Mara Salvatrucha inmates emphasis this. According to my Netflix it would appear that prisoners love to have a punch up and this leaked prison fight club video, from a facility in New Zealand, highlights that it doesn’t just happen on the screen, it’s happening within the walls.